1. Preventive Medicine Unit, Hospital de Dénia (Marina Salud), Dénia, Spain
2. Health Technology Asessment Unit, Agencia Laín Entralgo, Madrid, Spain
3. Primary Health Care, Area 8, Madrid, Spain
4. Preventive Medicine Service, Hospital Universitario de La Princesa, Madrid, Spain
5. Primary Health Care, Area 11, Madrid, Spain
6. Epidemiology Service, General Subdirection for Health Promotion and Prevention, Madrid, Spain